Papua New Guinea Water-base ink

1、 Overview
This ink is a printing ink system that uses water as the main solvent or dispersion medium. Its main components include water-soluble resins, organic pigments, solvents, and related additives. These ingredients are processed through composite grinding, making water-based ink particularly suitable for packaging and printing products with strict hygiene requirements such as cigarettes, alcohol, food, beverages, pharmaceuticals, and children's toys. With the advancement of technology and the reduction of costs, its application scope is expected to further expand.

2、 Purpose
1. Can be printed in fields with strict hygiene requirements such as food packaging, pharmaceutical packaging, and children's toy packaging.
2. Can be used for cigarette label printing.

3、 Precautions

1. Water based gravure ink may have drawbacks such as lack of gloss, dust loss, and low concentration. When printing, it is recommended to use it more for internal printing to achieve clear text, complete dots, strong color development, and clear layering effects.
2. Due to the high solid content of water-based ink, the dry ink film thickness can be smaller for the same area. Therefore, for ink holes with the same surface area, they can be engraved shallower.
3. Water based ink is weakly alkaline, which can easily generate bubbles during the printing process, leading to quality issues such as white spots and sand holes on the printed product. About 1% defoamer can be added to avoid these problems.
4. Water based ink is mainly evaporated and dried, with a certain degree of reactive drying. It is important to control the temperature of the hot air to avoid the surface of the ink from drying out but the interior from not drying thoroughly, or to prevent the ink layer from dissolving in water due to too fast a drying speed, which can make cleaning difficult.
5. Water based ink cannot be mixed with other solvent inks, otherwise it may cause quality problems.
Due to the volatility of alcohols and amines, the pH value of ink is prone to change. During the printing process, it is important to regularly add corresponding additives to maintain pH stability.
In addition, there are some specific technical issues and their solutions that need to be noted, such as shadow (fog) phenomenon, low printing plate durability, uneven transfer of solid plates, sticking (blocking) plates, and inconsistent plate color. These issues may be caused by various factors, such as the friction coefficient of the ink, blade wear, surface tension of water, hardness of the chromium layer on the printing plate, and changes in the pH value of the ink. Corresponding measures can be taken to address these issues, such as using wear-resistant scrapers, adjusting scraper pressure, polishing printing plates, using ethanol to reduce ink viscosity, cleaning printing plates, and controlling ink viscosity.